Understanding rodsAdam Royter | First Published: December 2004

This is the first article in a technical series that looks at how fishing rods are manufactured and how the various components that go into making a fishing rod will benefit you!

Roll an A4 piece of paper around a pen and pull the pen out. This is the basic principle of how a fishing rod blank is made. If you tap this rolled up paper against something it will feel fairly stiff and solid but if you try to flex it, it’ll fold. If you add one more sheet of paper, your tube will be twice as strong but also twice as heavy. Something to think about for later!

Since the late 1940s we have been using fibreglass to make fishing rods. In the mid-1950s, Don Green pioneered the hollow fibreglass fishing rod and in 1960 Jim Green’s (no relation to Don) passion for perfection in the action of rod blanks lead to the first ‘glass to glass’ ferrule.

Then, in 1973, Fenwick produced the first graphite fishing rod called HMG (High Modulus Graphite). It was from here that fishing rods would never be the same again!

Mandrels

Fishing rods need to be tapered. It’s the nature of the beast! We know that fishing rods are made from materials like fibreglass and graphite, but they certainly don’t grow out of your garden looking like they do!

Just like the pen and paper example we did before, graphite and fibreglass is rolled around a pre-determined steel form called a ‘mandrel’.

It’s these mandrels that will inturn decide things about the blank like its length, taper and how many pieces it is. It also affects the overall action of the rod, but this can vary quite considerably depending on how many wraps (or rolls) of which material go around the mandrel. Just like the pen and paper, the more sheets of paper you put in, the stiffer and heavier the paper tube gets!

Modern day machinery is giving blank designers the ability to create ‘multi-tapered mandrels’ which are broadening the scope of rod performance and allowing a greater cross section of fishing situation to be handled with the one rod.

Graphite and fibreglass are the two most used materials in the manufacture of fishing rods. In a lot of cases both materials are present in the one rod.

Graphite is lighter and stiffer (higher modulus) than fibreglass but fibreglass is more resistant to breaking (higher tensile strength). So finding a happy medium between these two is the job of the rod designer.

Most rod manufacturers use three different materials to make a graphite fishing rod blank. First, there’s the bulk of the material, which is the graphite itself. Then there’s a very thin layer of tightly woven fibreglass mesh called scrim and last but not least is the epoxy resin that holds it all together.

These materials are ordered by the rod manufacturer to its own specification and come on a roll, in a sheet form call pre-preg (pre-impregnated). These rolls must be kept in refrigerators in the dark to stop the highly unstable resins from spoiling.

Insert diagram 2

This diagram shows the graphite fibres, the scrim and the epoxy resin.

There are a lot of variations in the three components that go into this pre-preg and these variations can quite strongly depict how the rod will feel. With the major component being the graphite and the graphite’s stiffness to weight ratio or ‘modulus’ (look up Young’s Modulus) ranging from around 30 million up to 70 million modulus there can be quite an significant change in overall action of the rod.

Also, imparting massive action changes to the rod (and to my mind even more detrimental to the rod’s action than the graphite) is the resin type and quantity. Whether or not a fibreglass or graphite scrim (or any scrim at all) is used as a bonding agent and to help give the blank hoop strength, the resin is the component that will help give the blank its smash resistance and to keep the hole thing from falling apart!

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This shows one layer of graphite torn away from the rest exposing the whitish fibreglass scrim between the layers.

The process

Once a mandrel has been selected and the graphite pre-preg type chosen a specific pattern must be cut out of the pre-preg. This pattern will inturn give the blank a lot of its action.

Because fishing rods are, for the most part, lighter in action in the tip than in the butt, there needs to be less wraps of graphite in the tip than in the butt. This increasing amount of graphite, combined with the taper of the mandrel, will give the blank a graduated light, medium to heavy action from tip to butt.

Insert Diagram 3

This provides an idea of what a slow, medium and fast action rod blank pre-preg pattern would look like. Note that the fast action pattern has an extra inlay section of graphite to help beef up the butt section.

The pattern is cut and then it’s tacked onto the mandrel with a hot iron or glue. This is usually done down the straight edge of the pattern with the tip of the mandrel facing the thin end of the pattern. From tacking, the mandrel and pattern go straight to the rolling table where the graphite pre-preg is rolled around the mandrel under super high pressure.

It’s then taken to a special machine where it’s wrapped under extreme pressure with a heat resistant cellophane type material from butt to tip. What this does is sandwich the pre-preg graphite between the mandrel and the cellophane so tightly that when it’s curing in the oven the resin will work its way through the various fibres and stops the resin from dripping off the blank. It also expels any air bubbles that might have been trapped from the rolling table.

The piece is then put into an oven for just under an hour where the epoxy resin will start to cure. From there the cellophane is carefully cut from the blank and the mandrel is pulled out from the centre.

It’s at this point that some blank manufacturers will sand off the excess resin that has made its way to the out side of the blank. This can be visibly seen on rods as the ones that have not been sanded have a very faint ribbed affect on them.

Insert pic 1B

Here is one rod blank that has been sanded and one that hasn’t.

The effect of sanding the excess resin off the blank will lighten it and make it more responsive. On the other hand blanks that are un-sanded tend to have better resistance to light knocks and scratches.

That’s a very crude look at how a rod blank is made and now its time to dive into how all of this is going to benefit you!

What’s what?

We’ve looked at how a graphite rod is made. A fibreglass rod is no different. But if you want to put these two rods side by side and look at the fishable differences, then will start to see the tracks widen!

We’ll start by lining up the two materials, graphite and fibreglass, and going through some points.

- Graphite is lighter and stiffer (has a higher modulus) than fibreglass and can make a faster action and lighter weight blank.

- Fibreglass is stronger than graphite and makes for a more robust and durable rod blank.

- Because graphite is lighter than fibreglass (more to the point is the fact that you need less of the given material to make the appropriate rod there for the blank becomes lighter!) it creates much less physical fatigue.

- Fibreglass has more elasticity than graphite and is used in the manufacture of a lot of baitfishing rods to obtain a light bite indicating tip section.

- With the physical weight of a graphite rod and the recovery that can be obtained in the extra fast actions, super high rod tip speeds can be created (upwards of 250km/h) which in turn gives great distance and accuracy.

- Greater amounts of fibreglass can be found in graphite fly rod blanks to help slow recovery for a more moderate casting stroke and lighter presentation.

There are for and against for both parties but the truth be known, graphite is a more superior product to build fishing rods with. Evolution gave it to us and some 30+ years on where all still using it.

Graphite rods are a bit like Ferraris – you have to treat them nicely or they’ll end up a bit shorter at one end! Thankfully, rod manufacturers are quick to wake up to the point that not all of us have the hands of a surgeon and the finesse of a ballroom dancer! Some of us will always have hands full of thumbs and the subtleties of a pair of hessian underpants.

In this case, you should look for your next rod to have the best of both worlds! Composite is the word you need to look for. Shakespeare’s Ugly Stik range of rods has had this corner of the market sown up for well over 20 years. With a graphite inner and a fibreglass outer, they pioneered the composite rod blank market.

Fortunately for us, and unfortunately for them, there are now over half-a-dozen different manufacturers using this technique. This type of rod is best suited raw beginners, bait anglers and/or people how will never look after there rods!

If performance is more your style, there’s no going pass a top quality graphite rod for the simple reason that they outperform fibreglass and composite rods on almost every level.

Although I’ve just touch on the very basics, I hope some of you now know a little more than you did before!

Until next time

Fishing rods are by no means bomb proof. They are fine instruments of a sport we love and should be treated as such.

So, next time you go to throw the rods into the boat, spare a thought for their very thin walls and very fine tip and they’ll all live to fight another day! Oh, and don’t ever lend your good rods to your mates!

The lingo

Action – This refers to where the rod blank flexes. Blanks are generally categorised into four classes; slow, medium, fast and extra fast. The action of a rod can be changed either by the materials it’s made from or the taper that it’s built on. In most cases, the taper will have more to do with the action of the rod than the materials.

Recovery – This refers to how fast the tip of the rod can go from being flexed, back to its straight position. At the slowest end of the recovery scale you would find a slow actioned fibreglass rod and at the fast end, an extra fast graphite rod.

Power – The power of a rod is the rods resistance to flex under load. This is usually marked on a rod by the manufacturer using the code numbers or a line class rating. In the case of a line rating, the manufacturer gives you a ‘happy medium’ breaking strain of lines to which the particular rod is suited. For example: a 2.1m snapper rod with a line class rating of 6-8kg has recommended a physical power rating from 0-2.4kg. That’s to say that the upper line class rating of the rod set by the manufacture is 8kg. The recommended drag setting of one third of the breaking strain of the line equals 2.4kg. What the manufacturer is trying to tell you is that it’s safe to apply 2.4kg of your own physical strength through the rod without any chance of you breaking it.

Don’t for one second think that because your rod has a line rating of 10kg that you can lift 10kg of fish out of the water with it! Don’t forget folks, that fish don’t weigh anything in the water. It’s when you pull them out of the water that they weigh something.

Also, the line rating on your rod has absolutely nothing to do with the size of the fish that your rod can catch!